The risk of cross-contamination and infection from needle sticks are well documented in the associated literature. These include the contraction of life threatening HIV virus, several strains of hepatitis and other blood and body fluid borne diseases.
Surgically implanted vascular access ports have been used by the medical community for many years. They are a means of allowing for the easy removal of blood for laboratory testing along with providing for the repeated infusion of medication with as little discomfort to the patient as possible. These ports are placed in the chest of the patient, with a catheter extending into a blood vessel.
The port is typically constructed of biocompatible metal with a thick elastomeric membrane septum that is positioned under the surface of the skin, but accessible to needle penetration. The septum makes it possible for a needle to penetrate the port to an inner septum chamber for the infusion of a drug through the needle into the port, followed by the needle's removal without leakage from the port. The purpose of the port is to allow for easy drug delivery without excess needle sticks to the patient, however, the thickness of the port's septum increases the potential of an inadvertent needle stick to the patient or care giver during the withdrawal of the needle from the port.
The type of needles used with the vascular ports are termed "Huber" angled needles. These needles are unique in that they contain a ninety degree bend halfway along the needle shaft and include handling/securing wings located immediately adjacent the bend. The bend in the needle shaft allows the handling/securing wings to be secured to the skin of the patient with tape while the port is in use.
Additionally, these needles can be attached to a coupling hub that is either integral with a base or supported by a base forming a needle assembly. In this configuration with the Huber needle engaged in the port, the supporting base rest on the patient's skin. This base can be provided with foam cushioning and a bottom adhesive surface for added comfort and stability. One such Huber needle assembly having those above mentioned features is "The Gripper(.TM.)" from SIMS Deltec of St. Paul, Minn.
The Huber needles are noncoring, which means that they are able to penetrate cleanly into the vascular port, much like a knife, but upon removal from the port, the port's septum closes completely. This is a very important feature with regard to leakage from the septum and also allows the septum to be accessed well over 1,000 times without damage to the septum.
To remove the needle from the septum, the care giver typically places his/her first and middle fingers on the port to support it. The fingers must be positioned on each side of the needle shaft to properly support the needle. Downward pressure must be supplied by the fingers during the needle's removal to stabilize the port. Care must be given, because excess drag from the needle's removal can cause the implanted catheter to disconnect from the port or pull the catheter out of the vessel. The other hand is used to remove the needle by grasping its handling/securing wings and using considerable upward force to remove the needle from the patient. The care giver, when removing the needle, may inadvertently counter this force by thrusting the needle back in the direction of the port toward the hand stabilizing the port, which can lead to a needle stick to either the patient or the care giver.
The earlier references disclose several attempts at addressing the needle stick problem. However, none of the proposed solutions are user friendly or low in cost. For example, the Madore device, U.S. Pat. No. 5,460,612, discloses a device with two convex shaped prongs arranged in a "V" shape that are attached to a handle. With this device, the needle must be carried to a sharps disposal device with the potential for needle sticks occurring during the needle's placement in the device. In addition, the Madore device is preferably made of stainless steel, which would necessitate its resterilization between use, making the device labor intensive and expensive.
The Thompson device, U.S. Pat. No. 5,571,092, discloses a cylindrical shaped hollow bodied device that is open with flaps, at one end, and contains a slot in the other, where the tips of a hemostat are placed through the slot to grasp and remove the needle. Upon grasping the needle with the hemostat tips, downward pressure is placed on the top of the cylinder, the needle is forced upward into the hollow body with the flaps preventing the needle from leaving the container. The Thompson device is awkward to use, the hemostat is difficult to manipulate through the slot in the top of the container and the device is relatively expensive.
The Doyle Extractor, by Safetech International, Inc. (U.S. Pat. No. 5,709,660), is a device that utilizes a disposable reverse hemostat type design, with the tips apart when the handles are together. The tips have slots in them to accommodate the needle. This device does not address the problem of needle containment once the needle is removed or the possibility of inadvertent needle sticks. Also, the potential for blood aerosol occurring is increased.
Although previous devices have attempted to accommodate all potential problems that can occur with the use of the Huber needles with vascular ports, improvements are still necessary. As the number of blood-borne diseases increases, the safety of all concerned increases. A device that is both cost effective and safe to both the patient and care giver is needed in the health-care industry of today.